Self-consistent dielectric functions of materials: Toward accurate computation of Casimir–van der Waals forces

Abstract

Research on theoretical calculation of Casimir–van der Waals (vdW) forces is characterized by a great number of inconsistencies and conflicting reports with widely differing results for many known materials, including water, contradicting experimental measurements. Despite its importance for conceptual advances in both fundamental aspects and practical applications, a universal framework for the accurate determination of Casimir-vdW forces is lacking. Here, we propose a universal theoretical platform for computing Casimir-vdW forces, accounting for the electronic dielectric constant, optical bandgap, density, and chemical composition. Using this methodology, we determine the dielectric function for 55 materials, over a wide range of photon energies, covering an extensive list of common metals, organic and inorganic semiconductors, and insulators. Internal consistency of the compiled data is validated using optical sum rules and Kramers-Kronig relations. We demonstrate that the calculated vdW forces based on these data match remarkably well with the experimentally measured vdW forces.

Intermolecular forces at ice and water interfaces: Premelting, surface freezing, and regelation

“…[29] This is a demanding requirement, because experimental measurements in the high energy region are far from trivial, while the modeling of the optical properties over such a large frequency domain is also difficult and controversial. [28,[30][31][32][33][34][35][36][37][38][39] In view of these difficulties, here we revisit the role of van der Waals forces in ice premelting, using a combination of experimental dielectric properties, [34,[40][41][42][43][44][45][46][47][48][49] DLP theory, [29,50,51] and Quantum Mechanical Density Functional Theory calculations (DFT). [52][53][54][55][56][57][58][59] These results are revised in light of our recent work on the structure, kinetics and thermodynamics of the icevapor interface, [20,21,38,[60][61][62][63] providing a consistent and comprehensive framework for the description of premelting films as a function of temperature and pressure.…”

Intermolecular forces at ice and water interfaces: premelting, surface freezing and regelation

“…[45] Improved parametrizations using the modern data for the electronic transitions have been proposed. [34,37,39] Unfortunately, the model by Wang and Dagastine is presented only in tabulated form. A fully parametrized form with detailed description of the MW region was presented recently, but exhibits refractive indexes in the near infrared which are somewhat too large.…”

“…[29] This is a demanding requirement, because experimental measurements in the high energy region are far from trivial, while the modeling of the optical properties over such a large frequency domain is also difficult and controversial. [28,[30][31][32][33][34][35][36][37][38][39] In view of these difficulties, here we revisit the role of van der Waals forces in ice premelting, using a combination of experimental dielectric properties, [34,[40][41][42][43][44][45][46][47][48][49] DLP theory, [29,50,51] and Quantum Mechanical Density Functional Theory calculations (DFT). [52][53][54][55][56][57][58][59] This results are revised in the light of our recent work on the structure, kinetics and thermodynamics of the icevapor interface, [20,21,38,[60][61][62][63] providing a consistent and comprehensive framework for the description of premelting films as a function of temperature and pressure.…”

First-Principles Simulation of Dielectric Function in Biomolecules

“…Detailed knowledge of the dielectric response in the frequency domain is particularly important for the calculation of the dispersion van der Waals interactions [ 14 ], which are expressed as a non-local functional of the dielectric spectrum at imaginary frequencies in the Lifshitz macroscopic theory [ 3 ]. Notably, the first computation of van der Waals interaction with full spectral resolution was performed for a biophysical system of interacting phospholipid membranes [ 15 ].…”

“…Even though the dielectric properties of various metals, semiconductors, and insulators, organic as well as inorganic, have been critically assessed in great detail [ 14 ], the dielectric spectrum data for proteins and polypeptides mostly lack the relevant details regarding the optical properties in a wide frequency range from zero frequency to the far ultraviolet [ 18 ]. In the absence of relevant experimental data, the calculated ultraviolet frequency region dielectric spectra for the cyclic tripeptide RGD-4C (1FUV) [ 20 ], based on an ab initio quantum mechanical (QM) computational scheme, were successfully used to calculate the oscillator strengths, oscillator frequencies, and the relaxation parameters that enter the calculations of the van der Waals interactions in proteinaceous systems [ 19 ].…”